He said information about patients who received care very quickly was left out of the analysis for technical reasons.
"They are valid numbers," he said of audit results issued Monday, but acknowledged that the exclusion of those receiving swift care and other factors led to longer average reported wait times for some facilities than actually experienced by veterans.
One reason for the disparity is that the audit essentially represented a look into future doctor visits, while another VA data system assessed wait times by looking at the past, Matkovsky said.
The bottom line, though, he added, remains unchanged: Many veterans are still waiting too long for care.
"Nobody should wait 90 days for an appointment from when they want to be seen," he said.
Since Monday's release of average wait time data by VA headquarters officials in Washington, administrators at local VA medical centers have been questioning the announced audit results, saying they didn't jibe with internal data showing far shorter waits. The complaints have come not only from places that fared the worst in the audit, but also from hospitals that ranked in the middle or did relatively well.
"Our numbers are significantly better than what was released," said Dr. Jeffrey Ryan, the associate chief of staff at the Jesse Brown VA Medical Center in Chicago. The audit had pegged average wait times there for new primary care patients at 41 days. Ryan said the real wait was a fraction of that, typically just a day or two.
At the Durham VA Medical Center in North Carolina, officials said they were baffled after the audit singled them out as having a whopping 104-day average wait for new patients seeking mental health services. They said the VA's national scheduling database pegged the overall average wait time this year for the same category of patients at 25 days.
Beth Brown, director of the Louis A. Johnson VA Medical Center in Clarksburg, West Virginia, said her most recent batch of data for April showed new patients waiting an average of eight days for primary care, 21 days to see a specialist and 11 days for mental health services. The audit had entirely different numbers: 54 days for primary care, 86 days for a specialist and 96 days for mental health services.
For the audit, investigators essentially took a snapshot of all appointments in the VA's medical scheduling system as it existed on May 15. At that time, there were about six million visits that had been scheduled but hadn't yet taken place. The average wait times in the audit report were based on the time elapsed between when those appointments were requested and when they were scheduled to occur.
By contrast, the data systems traditionally relied on by local VA staff to examine wait times is based on historical data — meaning, appointments that have already occurred. That data may not be reliable either; the VA is investigating widespread manipulation of appointment data by schedulers.
The forward-looking audit released Monday doesn't account for appointments that might be rescheduled or cancelled, or moved up as doctors' schedules open up. It also omits same-day appointments and many other appointments for people who got care within a few days of first requesting it.
Those factors have the effect of inflating average waiting times — sometimes by a lot — although they don't erase the fact that thousands of people have been forced to wait weeks or even months for care they wish they could have right away.
Matkovsky said that the VA will make both sets of data available to hospital administrators going forward, so they can see how they performed in the past, and also get a picture of how their appointment calendars are shaping up in the months ahead.
The main purpose of the audit wasn't to get more accurate statistics on wait times, but to determine the breadth of inappropriate scheduling practices that occurred at some facilities that hid long waits for care. Some 13% of schedulers surveyed by the auditors reported being told by supervisors to falsify appointment records to make patient waits appear shorter. The VA inspector general has cited a since-abandoned performance bonus system as a reason for the falsifications.